1. Field of the Invention
The present invention relates to a hinge apparatus that foldably and slidably links a first housing and a second housing, and a portable electronic device including the hinge apparatus.
2. Description of the Related Art
In recent years, forms of portable electronic devices are diversified. Mobile telephones are typical examples of portable electronic devices. Conventional forms of a mobile telephone include a slide-type mobile telephone having two housings linked linearly slidably, and a fold-type mobile telephone having two housings linked by a hinge.
A slide-type mobile telephone can be folded up compactly by sliding and overlaying the two slidably linked housings. Generally, a first housing includes a display unit on an upper face thereof and slides along an upper face of a second housing, which includes an operation unit having multiple keys on the upper face thereof. Accordingly, the display unit is revealed constantly to an exterior; and the operation unit is revealed or hidden by sliding the first and second housings. Many slide-type mobile telephones can be operated even in a folded state by including operation keys disposed beside the display unit on the upper face of the first housing, or by including a touch panel display unit. Thus, the slide-type mobile telephone has excellent operability because the slide operation and the key operation can be easily performed even with one hand.
On the other hand, a fold-type mobile telephone can be folded up compactly by folding and overlaying two housings linked by a hinge. Generally, the fold-type mobile telephone can be folded such that a display unit provided on the first housing and an operation unit provided on the second housing face each other for protection. Further, mobile telephones disclosed in Unexamined Japanese Patent Application KOKAI Publication No. H11-30226 and Unexamined Japanese Patent Application KOKAI Publication No. 2003-174495 include two housings linked by a double-axis hinge. Thereby, the first housing and the second housing can be mutually pivoted; and additionally, the first housing can be rotated around a second axis perpendicular to the pivot axis. Accordingly, the fold-type mobile telephone including a double-axis hinge has diversity of form; including, for example, folded form with the display unit facing to the exterior.
Also, in a portable terminal disclosed in Unexamined Japanese Patent Application KOKAI Publication No. 2007-116709, a first housing and a slide module provided on a second housing are linked by a hinge, and a pivot axis of the hinge is arranged parallel to a sliding direction of the slide module. Thereby, the first housing and the second housing can be mutually pivoted; and additionally, the first housing and the hinge can be slid with respect to the second housing in a pivot axis direction.
However, a fold-type mobile telephone using a double-axis hinge has poor operability in comparison to a slide-type mobile telephone. In other words, in a fold-type mobile telephone using a double-axis hinge, it is difficult to change the form with one hand; and when the mobile telephone is folded with the display unit facing the exterior, the screen display is vertically inverted. Further, employing a double-axis hinge results in a large hinge unit. Also, the portable terminal using the hinge and the slide module described above has problems of a complex structure of the slide module and a large housing.